As the U.S. Supreme Court delivered its decision to uphold the Affordable Care Act Thursday, Duke Law faculty offered detailed analysis to media.

The court, with Chief Justice John Roberts writing the majority opinion, ruled that the individual mandate to purchase health insurance — the heart of the law and the most controversial of its provisions — is constitutional under Congress’s authority to levy taxes. The decision appears to agree with a view of the tax power developed by Duke Law Professor Neil Siegel and UC Berkeley Law Professor Robert Cooter in a forthcoming law review article (read the article on SSRN; read a summary on Balkinization). “Arguments by liberal scholars who care about constitutional text and history, such as Neil Siegel of Duke Law School, were reflected in Chief Justice Roberts’s opinion about the taxing power,” wrote Jeffrey Rosen in The New Republic. In a Volokh Conspiracy post, Professor Randy Barnett of Georgetown also said Siegel and Cooter seem to have "anticipated" the Chief Justice's approach in their paper.

“The court has long said that it doesn't matter what label Congress affixes to an exaction,” Siegel wrote Thursday in an NPR blog. “It’s a tax because it operates like a tax, giving people the choice to either obtain health insurance or else make a modest payment to the government if they choose to go without insurance.”

In a web discussion hosted by the National Constitution Center’s Peter Jennings Project for Journalists and the Constitution, Siegel commented on the Court’s rejection of the idea that Congress had the power mandate individual purchase of health insurance under the commerce clause, which allows lawmakers to regulate interstate commerce. “I do think it's significant and quite incorrect that the court disabled Congress from using the commerce clause,” he said, noting that most legal scholars, liberal and conservative agree that the minimum coverage provision is permitted under the commerce clause. “It was the tax power or nothing."

Guy-Uriel Charles, the Charles S. Rhyne Professor of Law, observed to Politifact that the Court did not technically label the provision a tax. "The Court said that the mandate is consistent with Congress' exercise of the taxing power, which is different from saying the mandate is a tax," he said.

In an essay for The Huffington Post, Duke Law Professor Jedediah Purdy welcomed the decision but expressed concern over the arguments set forth by the chief justice. “Justice Roberts’s opinion makes him a hero for a day to many liberals,” Purdy wrote. “It also moves the Court, at a stately pace, toward an aggressively right-wing view of the federal government's power. … Justice Roberts saved the constitutionality of a humane and centrist piece of social legislation. Gutting it would have been radical, and it is astonishing that four justices would have done so. He also confirmed the view of the Constitution that made the attack on that law seem plausible.”